I work with student data and assign identification numbers randomly to each student for confidentiality purposes. I use these identification numbers instead of their names. These identification numbers are ________. Note: I can only collect student information from those students who give me consent and after getting approval from Universitys Institutional Review Board (IRB) office.

A. Quantitative variable

B. Can be both quantitative or qualitative depending on purpose

C. Cannot be determined without more information

D. Qualitative variable